George Leslie Ltd

Key Facts

  • Client: Scottish Water
  • Engineer: Atkins
  • Conditions of contract: NEC 3 Option A
  • Contract value: £2.5m
  • Duration of works: May - Decembe 2017

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Wastewater Pipelines, Tunnels & Shafts

Dock Street CSO, Clydebank


The trunk sewer network in the Greater Glasgow area is designed to transfer wastewater to one of the four principal wastewater treatment works and this project formed part of the rationalisation and improvement to the network transferring flow to Dalmuir WwTW in Clydebank.

This project in Dock Street involved upgrading the Combined Sewer Overflow (CSO) and upsizing of feeder trunk sewers and was the largest in a £5m mini-cluster of six projects in the Yoker area.

The main elements of work involved approximately 200m of new sewers ranging from 900mm to 1.5m in diameter at depths of 4.5-5m, and the construction of a new 11.5m x 4m x 5.5m deep CSO chamber together with intermediate, large diameter manholes and a 4m diameter bifurcation chamber which had to be constructed around the existing live sewer.

Due to the cluster of live services on the only route for the pipeline, a 70m section of the 1500mm diameter pipeline was constructed by pipe-jack.

Overcoming the existing ground conditions which comprised the notorious Clyde Alluvial fill, together with the tidal effect from the adjacent River Clyde necessitated careful piling and extensive well-point dewatering. In addition, trench formation was strengthened with imported heavy aggregate laid on top of geotextile.

Careful phasing of the mini-cluster of projects was also required due to the extensive traffic management in the area.

News updates


The overall project involves the off-site fabrication and installation of a new linkspan structure at Oban Ferry Terminal for client Caledonian Maritime Assets Ltd (CMal).

12th February 2019

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GL return to the Sound of Kerrera

GL making a return visit to the Sound of Kerrera off Oban, to undertake substantial repairs to the breakwater which suffered collision damage following an altercation with a workboat earlier this year.

14th December 2018

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Polmadie Bridge official opening……..

Michael Matheson MSP and Cabinet Secretary for Transport, Infrastructure and Connectivity covered all his portfolios at the official opening of the new Polmadie Footbridge giving pedestrian and cycle transport access,

18th September 2018

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George Leslie Ltd, Blackbyres Road, Barrhead, Glasgow, G78 1DU  |  |  +44 (0)141 881 9131